Process and mechanism for separating intermixed divided materials



R. FEALE, JR 2,@7 D

PROCESS AND MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS July Original Filed March 25, 1926 4 Sheets-Sheet l Imnentor C(ttorneg- Jufiy 2, 1935. R PEALE, JR 2,7,98

PROCESS AND MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS Original Filed March 25, 1926 4 Sheets-Sheet 2 July 2 1%35. R, PEALE, JR Z,@@7,@9$

PROCESS AND MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS Original Filed March 25, 1926 4 Sheets-Sheet 3 I Imventor 276W M, 21.

attorneg 47 7644 @wld b R. PEALE, JR

4 Sheets-Sheet 4 Srmeutor g hm Original Filed March 25, 1926 E; 3 k mg Emily 2, 1935.

PROCESS AND MECHANISM FOR SEPARATING INTERMIXED DIVIDED MATERIALS Patented July 2, 1935 UNITED STATES PATENT OFFICE PROCESS AND MECHANISM FOR SEPARAT- ING ENTERMIXED DIVIDED MATERIALS Rembrandt Peale, Jr.,

Clearfield, Pa., assignor,

by mesne assignments, to Peale-Davis Company, Wilmington, Delaware Del., a corporation of Serial No. 614,109.

Again divided and this application April 12, 1935, Serial No. 16,093

43 Claims.

The invention is directed to a novel and useful process and mechanism for separating intermixed divided materials of different specific gravities; and more particularly to a process and mechanism for separating such materials which vary relatively greatly in the size of the intermixed fragments or particles, while on the other hand, varying relatively little in their specific gravities.

Objects and advantages of the invention will be set forth in part hereinafter and in part will be obvious herefrom, or may be learned by practice with the invention, the same being realized and attained by means of the instrumentalities and combinations pointed out in the appended claims.

The invention consists in the novel parts, constructions, arrangements, combinations and improvements herein shown and described.

The accompanying drawings, referred to herein and constituting a part hereof, illustrate one embodiment of the invention, and together with the description, serve to explain the principles of the invention.

Of the drawings:-

Fig. 1 is a central, vertical, longitudinal section through a mechanism embodying the invention;

Fig. 2 is a top plan, with certain parts in section, taken substantially on the line 2-2 of Fig. 1;

Fig. 3 is a full horizontal section taken on the line 33 of Fig. 1;

Fig. 4 is a full transverse, vertical section,

r taken on the line 4-4 of Fig. 1;

Fig. 5 is a side elevation of the right-hand end of Fig. 1 and of the table reciprocating means and the air pressure means located at the right thereof;

Fig. 6 is a diagrammatic plan showing a screen having areas of different size mesh;

Fig. 7 is a fragmentary elevation, on a greatly reduced scale, and partly diagrammatic, showing a modified form of the sorting mechanism;

Fig. 8 is an enlarged, vertical, sectional detail of one of the discharge regulating devices for the heavier material shown near the central part of Fig. 1;

Fig. 9 shows a different form of regulating discharge gate for the stratified heavier material;

Fig. 10 is a top plan of the table, partly diagrammatic, and. showing a form of discharging devices for the lighter Stratified material;

Fig. 11 is a transverse, vertical fragmentary section on the line I li l of Fig. 10, and

Fig. 12 is a view similar to Fig. 7 showing a reversed sorting system.

The present application is a division of my co-pending application S. N. 614,109, filed May 28, 1932, for Process and mechanism for separating intermixed divided materials, said application S. N. 614,109 being itself a division of my co-pending application S. N. 97,222, filed March 25, 1926.

The invention comprises a novel process and novel mechanism for separating intermixed divided materials, and delivering the different separated materials apart from each other and free from intermixture. The invention is directed more particularly to providing an improved process and mechanism whereby intermixed materials are successfully separated, wherein the fragments or particles of the'various materials vary very greatly in size, and wherein the various intermixed materials differ relatively but little in their specific gravities; the rapid and successful commercial separation thereof thus presenting a very difiicult problem.

The expression intermixed divided materials is used for convenience herein in designating a mixture comprising two or more materials in granular, fragmentary, pulverulent or other like state, whether natural or due to previous handling or operations. The expressions heavier and lighter as applied to the materials, pertain to relative specific gravities, and are so used for convenience.

An example of such materials, with the mechanical conditions and having the physical properties already described, is a mixture of coal, bone, and rock and other impurities, as it comes from the mine, and the present invention in actual practice has been chiefly directed to the automatic cleaning of the coal as it comes out of the mine, and without previous preparation or handling.

One of the principal and most valuable features of my process and mechanism is the ability to practically completely separate coal, bony and rock without the preliminary sizing which has heretofore been necessary, and which constitutes a tremendous, and practically prohibitive, item of labor and expense. By my inven tion, I am enabled to practically complete the separation of the coal, bony and rock, as it comes from the mine, from the finest dust up to pieces three inches in dimensions, by a single operation and by running it in very large volume over merely a single cleaning table, the coal going direct to the cars, and the rock to the rock heap, and the bony being handled in any way desired.

By my invention, I dispense with all of the screening mechanisms of the prior art and with all but one of the separating tables. I use only a single large separating table, and over this single table I send the unprepared, unsized, intermixed materials, which prior to my invention were necessarily sent first over the several screening or sizing mechanisms, and then over the corresponding separating tables, as described in the preceding paragraphs. I am able on this one table to practically completely separate the coal, rock and bony and other impurities from three inches in dimensions down to the finest dust.

My invention is applied to the separation or purification of unsized intermixtures of raw or impure coal such as hereinbefore described, and the invention provides several novel ways or systems for accomplishing the purification of a given raw, unsized coal mass. The various systems of treating the raw mass of unsized coal all comprise purification thereof by pneumatic Stratification in successive stages. That is, my separating table comprises a plurality of more or less individual separating zones adapted to maintain a plurality of individual beds or subbeds of intermixed materials undergoing pneumatic stratification and separation. Various subdivisions of the raw mass are subjected to separating action in the individual separating zones and are progressed or transferred in whole or in part from one zone to the other to thereby undergo successive purification treatments within the different zones and under the varying conditions prevailing in said zones. The particular system of subdividing the raw mass and of subjecting the various subdivisions thereof to successive pneumatic stratification actions will be dependent upon the characteristics and conditions of the particular raw coal or intermixture to be purified and the use of the different systems and instrumentalities will be regulated and coordinated in accordance with such conditions. In the capacity for varying the manner and degree of correlation and cooperation of the various process steps and instrumentalities to meet the varying requirements of successful and approximately complete separation with different kinds and conditions of intermixed materials lies in part the value of the invention.

In the various separating systems comprised by my invention, it will be understood that there is provided one or more continuous and forwardly flowing beds of the intermixed divided materials, such as the unsized mixture of coal, bony and rock, said beds of materials being supported upon an air-pervious deck while undergoing separation, through which deck air under pressure is passed from beneath upwardly through the bed of material, the deck at the same time being moved or reciprocated to mechanically forward the separated heavier material, which has settled down upon the table, by friction and inertia toward a place of delivery, the gradation of the force of the air currents, the table structure and the various coordinated instrumentalities cooperating in the novel manner hereinafter set forth to accomplish a desired result.

Referring now to the various systems fon effecting substantially complete purification of a. given mass of raw unsized coal or the like, in

one system (hereinafter called the first system for convenience of description) the entire unsized mass is fed to the first or rearmost zone of the separating table and passes in such completely unsized condition throughout the entire length of the table and successively through the various separating zones. The process of separation by stratification is continuous and progressive along the continuously maintained bed of materials as it passes successively from one separating zone to the next. The heavier material is delivered from the bed in a plurality of places or streams, preferably at the ends of the successive separating zones, while the upper stratum of clean lighter material travels longitudinally forwardly along the table and throughout the successive zones or sub-beds in a single stream. In one alternative manner of carrying out the process according to the first system, all the lighter material travels as a fiotant upper stratum the length of the table from the rear or feed end through the successive separating zones or sub-beds to discharge in a unitary, forwardly flowing, purified stream at the front end of the table, while the heavier material is discharged at a plurality of loci along the bottom of the table and preferably at the ends of the successive zones or sub-beds; and this manner or system of operation is preferably practiced with the mechanism illustrated in Figs. 1 and 2.

Alternatively and optionally, the discharge of the clean upper stratum of lighter material may be commenced medianly of the length of the table by lateral diversion of all or a portion of the clean, separated upper stratum and may be continued progressively along the table as the purifying and stratifying actions progress (Figs. 10 and 11). Usually and preferably the lateral diversion of the material in the upper stratum will be effected at or near the ends of the successive separating zones or sub-beds. Thus there may be effected a practically immediate and regulable discharge of both the lighter and the heavier materials, respectively, as soon as the separation thereof is gradually effected, this discharging action of both materials concurring along a great part of the length of the table.

In other systems of purification processing comprised by the invention the successive separating treatments are applied to certain size ranges or fractional portions of said size ranges from the raw unsized mass, said selected or predetermined size ranges being successively subjected to purification treatment in diflferent states of intermixture with respect to the other constituents of the raw mass. In said systems, the invention provides for sorting the material into two or three broad ranges of sizes to assist in the separating action, but avoiding the close sizing required by the previous practice.

In one of said systems (hereinafter referred to for convenience as the second) the finer particles of the raw coal are treated to successive pneumatic-stratification separating actions by passing said finer particles through the successive separating zones or sub-beds on the table. In one of said zones, there is formed a bed containing only the finer particles of the coal and impurities and said sub-bed of fines is subjected to a pneumatic-stratification separating process; while in another of the sub-beds or separating zones of the table the finer coal particles or a regulable portion thereof are treated in intermixture with the coarser pieces of the raw mass. In practicing said second system, the raw coal mass is preliminarily sorted. into two or three broad ranges of sizes, the finer sizes being fed to the rearmost separating zone or sub-bed on the table, while the coarser sizes from the raw mass are fed to the more forward separating zones or sub-beds. The fine impurities or heavier particles separated from the subbed of fines by the pneumatic-stratifying action are discharged at the forward end of said subbed or separating zone, while the flotant stratum of fine, pure coal and a possible unseparated residuum of fine impurities are progressed forwardly and into the next successive sub-bed where they intermix with the coarser coal and refuse therein. Thus the preliminarily purified finer particles of coal participate in the, pneumatic stratification and separation of the coarser pieces and at the same time themselves undergo a further separating action.

The invention provides for regulating the amount and condition of the fine particles so introduced into the sub-bed containing the coarser pieces; that is, the stream of preliminarily purified fines passing from the initial sub-bed of fines into the next successive sub-bed may consist of all the fine coal stratified and separated in the initial bed, or a regulable portion of said fine coal may be discharged directly from the first sub-bed and the remainder introduced into the successive sub-bed or beds as desired. Thus in the second system, all or a regulable portion of the finer coal particles are subjected to pneumatic-stratification separation action in a plurality of beds and in different states of intermixture with respect to the other constituents of the raw coal mass.

In another or third system, the coarser coal is subjected to purification treatments or actions in different states of intermixture with respect to the other constituents of the raw coal mass. The third system is substantially the converse of the second system, in that the coarser or coarsest size range of the raw coal segregated from the raw mass by the broad sorting action hereinbefore referred to, is initially purified in the first or rear bed and the coarser impurities or heavy material separated therefrom in the first separating zone. The coarse coal and possibly still-intermixed residual impurities are then introduced into the successive, forwardly-located separating zones where they intermix with the finer particles from the raw mass and there enter into the separating action of the sub-beds containing the resulting intermixture of the fine and coarse materials. Analogous to the operation of the second system, the coarse materials, delivered from the initial sub-bed into the successive sub-beds of finer material, may consist of the entire mass of coarse pieces: (except for the coarse heavy material discharged from the initial sub-bed), or a regulable fraction of said mass of coarse pieces may be intermixed with the finer particles, the remaining coarse pieces being discharged directly from the first sub-bed as clean coal.

Referring now to the general features of the pneumatic-stratification separation process as practiced in the various systems and in the several beds or sub-beds:

The invention, as embodied, provides broadly for feeding on the material, preferably in the manner hereinafter described, at such rate as to build up at the beginning, and thereafter to continuously maintain, upon the table, a bed of materials of substantially uniform thickness, which moves gradually forwardly over the table. The materials undergo a continuous and progressive separation, due to the combined air and mechanical actions, with the cooperation of the mechanical instrumentalities, as they move forwardly, gradually approaching complete separation, which is effected before the separated materials are delivered from the table, the discharge of one or more of the separated materials being likewise gradual longitudinally of the table as already explained.

By my present invention, the intermixed materials of the diverse and difficult character already described, are fed on to the rear end of the air-pervious table, and beginning at this time and continuing progressively forwardly along the table, by the air action, and partly by the reciprocation of the table, the intermixed particles or fragments of material are loosened apart and separated from each other, and the lighter material gradually settles and comes to rest upon the table, and thereafter is progressed forwardly by the combined action of friction and inertia to a place of delivery, the paths of travel of the separated strata and the manner of discharge thereof, as broadly indicated, cooperating to facilitate practically perfect separation, rapid action, and large output.

Broadly considered, in connection with the foregoing, the process and table of my present invention, in addition to creating this superior flotant stratum of the lighter material, provides also for this stratum traveling forwardly in a straight and unconstrained path and at the end of its straight and unconstrained path to be delivered from the table, thereby giving the shortest and most natural path to the superior flotant material.

In connection with the foregoing, the air action is cooperatively proportioned and controlled to produce the completest and most satisfactory result in the difficult task of completely, or practically completely, separating the particles of intermixed material of such widely divergent dimensions and so closely related in relative specific gravity. Accordingly, the air chamber beneath the air-pervious deck or table, is preferably divided into a plurality of sub-chambers and the entry of the air into the various sub-chambers, and the amount and direction of the air currents passing through the deck and the bed of coal in the separating area or zone forming the top of such chamber, is nicely controlled by devices which regulate the amount and direction of the air currents which enter the chamber. Preferably a series of baffles or vanes are movably mounted in the vibrating or reciprocating air chamber, and are thus positionable to control the air currents between zero and full force thereof.

The foregoing general description and the following detailed description are both explanatory and illustrative of the invention, but are not restrictive thereof.

Means are provided by the invention for supplying and maintaining upon the table a bed of the intermixed, divided materials undergoing separation, and for supplying the intermixed materials at such regulable rate as to maintain a bed of practically constant or uniform thickness, or of such varying thickness as may be most efiicient and advantageous for the particular work being done and materials being operated on. In conjunction therewith, means are optionally provided for sorting the material into two or three broad ranges of sizes, to assist in the separating action, but avoiding the close sizing required by the previous practice.

This broad sorting provided by my present invention, separates the materials into only a few ranges of sizes, and delivers the broadly sorted sizes to different loci or zones along the table. Such a sorting also does not require the use of more than a single table to completely separate the materials as they come from the mine, except for breaking very large lumps, and does not require any of the separate sizing machines.

So far as concerns many features of the invention, the sorting means may be entirely dispensed with, and the intermixed, divided materials fed directly to the table in the manner already described. This direct feeding of the intermixed, divided materials may be found preferable for certain classes or conditions of the materials to be separated and will be practiced in the first system hereinbefore referred to. With this option and adaptability in view, the sorting device is detachable from the separating table, for use or not, as may be desired.

In accordance with certain features of the invention, the separating action occurs in successive stages forwardly along the table, there being a discharge of the heavier stratified and separated material at relatively far separated successive points longitudinally of the table. The means for effecting the discharge of the heavier material, so far as separated, are provided with devices for safe-guarding against the discharge of the lighter material with the heavier material. Means may be optionally provided at corresponding points or zones along the table for effecting partial discharge of the lighter and superior stratum of separated material so far as stratified and separated up to that point; or the lighter and superior stratum may be progressed forwardly along the table and entirely discharged from the front end thereof. It will be understood that the sorting mechanism may be utilized with the foregoing or not, as may be most efficient or desirable.

Referring now in detail to the present preferred embodiment of the invention, illustrated by way of example in the accompanying drawings, means are provided for supplying the intermixed, divided materials at such rate, and in such quantity, as will preserve upon the table a bed of materials undergoing stratification and separation of the desired or required thickness. In the embodied form of material-supplying means, a hopper l is provided, having side walls 2, and inwardly and downwardly inclined front and rear walls 3 and l. The hopper is supported by suitable means, such as cross beams 5 and 6. The hopper is preferably of such width as to feed on the intermixed divided materials entirely across, or substantially entirely across the width of the rear end of the table, but the feed may be narrower if desired.

The lower end of the hopper has an opening therein, and beneath this opening is a horizontally-disposed, hemi-cylindrical plate I, having a material discharging opening at the front side thereof. The material discharge regulating devices comprise a horizontally-extending shaft 8, located within the plate I, and suitably journalled at either end thereof. Fixed to the shaft 8 are a plurality of spaced-apart discs 9.

Fixed to, and extending between, the discs 9 are a plurality of horizontally-extending feed plates in, which are preferably arranged tangentially to the shaft 8. A variable speed driving means for rotating the shaft 8 is provided, of any known or suitable form, whereby the speed of the discharge of materials from the hopper I to the table may be nicely regulated as desired.

The preferred form of the invention will be described as employing the broad sorting device, although it will be understood that the use of this device is entirely optional so far as concerns most features of the invention. When the sorting device is dispensed with, there may be a chute for directing the intermixed materials directly from the feed regulating means, already described, to the bed upon the table, or the hopper may be arranged and located more closely to the table.

The embodied form of the sorting device shown in Fig. 1 comprises a screen 20, having a transversely-disposed rear end wall 2|, and two side walls 22 and 23, the front end of the screen being open. The bottom 20 is composed of bars or meshes of various sizes, whereby the pieces of the intermixed materials within very wide size limits are deposited in various areas of the bed of materials, as may be found most eflicient in separating the particular kind and condition of intermixed materials. The sorting device is detachably mounted, by means of bolts or otherwise, upon a series of supports 25, 21 and 28, which are mounted upon the table structure. With the arrangement shown in Fig. l, for carrying out the second system of purification the finer or smaller pieces of intermixed materials are fed to the rear end of the table of materials being separated upon the table, an intermediate size being fed to an area forwardly along the table, and the larger sizes of the intermixed materials being fed toward the forward end of the table. A reverse arrangement for carrying out the third system is also shown (Fig. 12) and will be later described.

In Fig. I chutes 29 are shown below the sorter 20, whereby all the materials within a predetermined range of sizes are deposited upon the bed at the rear end of the respective separating zones or areas upon the table. In the arrangement of Fig. 1, the materials within a predetermined range of sizes is delivered all over one of the zones or areas of the table. If the sorter, either of the form shown in Fig. l or Fig. 7, is reversed, the places of discharge of the various sizes will also be reversed, and such reversed arrangement, for carrying out the third system, is shown in Fig. 12.

In the embodied form of my invention, the table and the upper portion of the air chamber reciprocate together, while the lower part of the air chamber is stationary. Means are provided for varying the air-current action through the bed of materials, and this variation in the air-current action may be effected by varying the perviosity of the table in different areas thereof, or by varying the intensity of the air pressure in different sections or compartments of the air chamber, or it may be effected by a combination or cooperation of these. In the embodied form, both these means are exemplarily illustrated.

In accordance with certain features of the invention, and as already indicated, the table is divided into a plurality of separating areas or zones, shown as 39, 39a and 39b, there being discharge means for the heavier Stratified and.

separated material for each of these areas, there being also optional discharge means for the lighter and superior stratified material for each such table zone or area.

As embodied, beginning at the rear end of the table, a separating table zone or area 39 is provided, consisting of a perforated metal plate, or wire mesh, or other suitable material, for permitting the air currents to pass therethrough and through the bed of materials above. The plate 39 is supported in any suitable manner, as by angle frame members 40 at the end, and 4| at the sides, and 42 at the front, the angle strips being attached to the side walls of the air chamber. The plate 39 is thereby detachably mounted and is interchangeable with other plates of the same or different degrees of air perviosity as may be desired or required.

The table is provided with a transverselydisposed, upwardly-extending rear retaining wall 43 for the bed of materials thereon, and also with upwardly-extending, longitudinallydisposed side-edge, bed-retaining walls 44 and 45, for maintaining the bed of materials upon the table. As a convenience in structure, the retaining walls for the bed of materials upon the table may be an integral continuation of the transversely disposed rear wall 49, and the longitudinally-disposed side walls 50 and 5|, of the vibratable or reciprocable part of the air chamber. The air chamber is also provided with a transversely disposed front wall 53.

At the forward or front edge of the zone or area 39 of the table, means are provided for discharging the heavier material in so far as it has become stratified and separated upon the table 39. In the embodied form of such means, a transversely-disposed opening 5! is provided extending for relatively a short distance across the front end of the part 39. At either side of the opening 5i there is a vertically-disposed wall, guide portion 58 and 59, extending from the opening to the side walls 50 and 5|, and being preferably inclined inwardly and forwardly from the side walls to the adjacent side of the opening 5'1.

In cooperation with the opening 51, means-are provided for regulating the discharge of the rock or other heavier material through the opening. Thus all of the rock or other heavier material which has become stratified on the area 39, and is consequently at rest upon the table, will be discharged at this point, while all the separated lighter material, and those portions of the material which are still intermixed, will be prevented from discharging at this point. In the embodied form of such means, a gate 60 is hinged at 6| along its top edge, which may be regulably set, as by weights 62, to control the discharge of the material as desired.

Means are provided for causing a back air presssure against the rock or other material at the gate 90, when desired, and also devices for discharging the rock without interfering with the operation of the air chamber. In accordance with this feature of the invention, the rock, or lie material discharges through opening 51 into a vertically-disposed chamber '59, located just ahead of the opening 5'8, and in the central part of the table. The separated rock or other heavier material from the area 39 is discharged into this chamber l9. To control the discharge of the separated rock from the chamber, a bottom gate 89 is provided, fixed to a shaft 8|, journaled in the side walls of the air chamber. The shaft 8| has a crank arm 82 at the end thereof, and. located on the exterior of the machine, and a pin 83 is insertible in and removable from a hole in the side wall of the air chamber, whereby the gate 80 is retained in horizontal position but on occasion may be swung to vertical position to discharge the rock from the chamber 19.

The chamber 19 is directly above another vertically-disposed chamber 85, preferably of similar size and shape built into the stationary or non-reciprocable part of the air chamber, and there is a flexible, air-impervious connection 85 between the bottom end of chamber 19 and the top end of chamber 85. In the bottom part of the chamber 85 is a horizontally-disposed gate 81, fixed on a shaft 88, journaled in the side walls of the chamber. The shaft 88 has an arm thereon similar to the arm 82, and the retaining pin 83 to hold the gate 80 in horizontal position.

To provide air-pressure against the gate 60 of the opening 51, there is an opening 9| from the air chamber into the chamber 19, and a closure 92 of any suitable form may be provided which is regulably positionable to control the air action in the chamber 79 against the gate 60, and against the rock or other heavier material,

which is being discharged through the opening 51. As embodied (Figs. 1, 3 and 4) the sliding closure 92 has a rack 93 thereon, and a pinion 94 meshing therewith. Pinion 94 is fixed on a shaft 95, journaled at 95 on the walls of the box 19. Shaft 95 extends outside the air chamber and has a crank arm 91 on this exterior end.

After a mass of rock has accumulated in the chamber 19, the pin 83 may be withdrawn, and the gate 80 will be rocked to discharge the rock into the chamber 85 where it will rest upon the gate 81. The gate 80 will be again closed and secured after the discharge of the rock, thereby cutting off the air pressure from the chamber 85. The gate 8'! may then be swung to discharge the rock from the chamber 85 onto an endless conveyor belt |0|, which runs over a plurality of guide rollers I02, to convey the discharged rock away to any convenient place of discharge.

As one means for regulating the air pressure action through the bed of materials, a plurality of adjustable bafiles H13 are shown, disposed transversely in the air chamber, and fixed respectively on a shaft I04, journaled in the walls of the air chamber. The shaft I04 is provided externally of the chamber with means for positioning the bafiles to control the air current action in the zone 39 of the table, such as hand wheels I 05. In Figs. 1 and 3, the baffles or vanes I03 are shown extending completely across from one vertical wall 50 to the other vertical wall 5| of the air chamber, and adjacently located as a longitudinal series extending in substantially the same horizontal plane lengthwise of the air chamber. As shown in Fig. 3, the baffles or vanes 03 are positioned and proportioned so that when the respective adjacent bafiles or vanes are turned into the horizontal position, their adjacent edges abut or overlap. For example, if the group of baffles or vanes I03 at the right hand end of Figs. 1 and 4 were turned somewhat farther in a counter-clockwise direction, their adjacent edges would substantially abut or overlap, as shown by the dotted lines in Fig. 1. In that position, the bafiles or vanes constitute a substantially complete cut off for the air currents in the corresponding part or area of the table. The intensity of the air current action in such area will be determined by the number of the baflles or vanes I03 which are turned into any desired or required angular position. When the members I03 are turned to the vertical position, as shown at the left hand end of Figs. 1 and 3, the members I03 permit substantially the full volume of the air currents to pass upwardly to the air-pervious table.

The vanes or bafiles I03 can be turned to any desired intermediate positions or extent between the vertical and horizontal, and in any combinations, and for any particular areas of the table, as desired. Furthermore, the members I03 may be inclined in either direction, that is, with their upper edges directed either forwardly or backwardly with respect to the front and rear ends of the table. As shown in Figs. 1, 3, 4 and 6, the vibratable or reciprocable part of the air chamber is divided into a series or plurality of separate chambers by vertically disposed partitions or walls I00, the baflles or vanes I03 being shown mounted in the lower part of the various chambers thus formed by the partitions or walls I00, and when in a horizontal position, they form a floor for the chamber. The air chamber is, as described, preferably formed into a plurality of sub-chambers, in each of which, independently of the others, the amount, and also the direction, of the air currents may be varied in any degree between being wide open and being entirely out off, by the setting of the bafiies or vanes I03 in each of the sub-chambers, irrespective of the air current settings in the other chambers. Thus, the amount of the air currents passing through them for any desired area, and any desired part, of the air-pervious table can be closely regulated, and the air currents for the various selected areas and parts of the table can be likewise deflected and directed as may be desired. Also the air current pressure or action through the bed of coal undergoing purification may be regulated in any desired number of areas of the table, that is, practically within the smallest or greatest areas necessary in commercial operation, to meet difficult and changing conditions of the bed, such as differences in thickness of different parts of the bed, the proportions of different sizes of coal in any particular areas of the bed, or any other conditions of commercial coal purification.

In the embodied form of reciprocable table, the bafiies or vanes I03 are mounted in the upper part of the air chamber which reciprocates with the table, and by means of the hand wheels I05 they may be regulated as minutely as desired while the table is running.

The separating table comprises a plurality of successive zones 39, 39a and 391), having the same manner of operation, and, preferably, substantially the same structure as that already described, and the various structural features common to the successive zones or parts of the table will be indicated by the same reference numerals.

The second separating zone or area I01 of the table may be air pervi'ous throughout its entire extent, but preferably the portion I08 thereof, which constitutes the top of the chamber 19 is preferably air impervious, for the purpose of avoiding disturbance or complication of the air pressure control within the chamber 19 and against the gate 60. It will be understood, however, that the desired action and function as already outlined may be effected with regard to the material discharging from the area 89 into the chamber 19 and at the same time have an upward air action through the part I08, just above the chamber 19.

In the embodiment illustrated in Fig. 1, and as already described, the superior stratum of separated lighter material, such as coal, is entirely discharged from the forward end of the table. For this purpose at the forward end of the table, there is provided a downwardly-inclined chute III, extending entirely across the table, and having an extension II2 discharging onto an endless conveyor belt II3 journaled to run over rollers H4, which are mounted in a suitable frame II5. In accordance with certain features of the invention, however, means are provided for discharging the superior stratum of separated coal, or other lighter material, from the different areas where portions thereof have been separated and stratified, and this feature of the invention will be later described.

Referring now to the mounting of the table and upper part of the air chamber for reciprocation, a plurality of supporting arms Il9 are pivoted at their bottom ends I20 to the upper part of the side walls I2I of the non-vibratable part of the air chamber. The arms H9 at their upper ends I2I are pivotally connected to the lower part of the respective side walls 50 and BI of the reciprocable or vibratable part of the air chamber. A flexible air-impervious envelope I 22 has its lower edges making air-tight connection with the upper edges of the non-reciprocable part of the air chamber entirely thereabout, and has its upper edges making a like air-tight connection with the lower edges of the reciprocable part of the air chamber.

Suitable cushioning means are preferably applied to the bed to control or ease the vibration thereof, and this means may be of any known or suitable form. As embodied, inclined blocks I21 are shown fixed to the under surface of the side walls of the reciprocable air chamber and corresponding disposed blocks I28 are fixed to the upper edge of the lower or non-reciprocable part of the air chamber. Coil springs I29 are in compression between these blocks and may be provided with tension-regulating devices of any known or suitable form as may be desired. If desired, or required also, reversely acting spring cushion means may be provided.

Any form of table-actuating or reciprocating means may be provided so far as concerns most features of the invention. As embodied, a heavy link I35 has a pivotal connection at I36 with a bracket I31, fixed to the lower part of the rear end wall of the reciprocable portion of the air chamber. At its opposite end the link I35 is connected at I38 with a wrist pin, eccentrically carried by crank plates I39, suitably journaled on a supporting structure. The link I35 is also preferably provided with a length adjustment I40.

The embodied form of driving means comprises a worm-wheel I4I fixed on the shaft of the crank plate I39, and it meshes with a worm I42, having bearings I43 and I44 in a bed plate I45, carried upon a support I46, which in turn is carried on supports I41 from the floor. The worm I42 is driven by a motor I48. It will be understood, however, that any known or suitable form of speed-reducing, powertransmitting connections may be used between the motor and the table reciprocatingmechanism as may be found suitable or desirable.

The air-current or air-pressure creating means, in the embodied form, comprises a blower I56, mounted in a housing II, which discharges the air current into a conduit I52. In accordance with one feature of the invention, the entire table is relatively inclinable, to vary and control the separating action, this means being preferably applied to the non-reciprocable part of the air chamber. With this in view, there is a flexible, air-impervious connection I53 between the air-current conduit I52 and the part I54 of the conduit, which latter discharges into the non-reciprocable part of the air chamber.

The non-reciprocable part of the air chamher is provided with pivotal mountings I55 and I56 near the rear end of the side edges thereof, said mountings comprising pins I56 carried in brackets I51, fixed to the air-chamber structure, and extending downwardly therefrom. Pins I59 are also journaled in brackets I58 carried on supports I 59. Near the forward end of the air chamber there is a cross beam I63, upon which the chamber rests, and near either end of the beam I69 are ball-and-socket bearings I64, provided with downwardly-extending, screwthreaded rods I65. Threaded on the respective rods I65 are nuts I66, resting upon the top face of cylinders I61, carried on supports I68. By turning the nuts I66, the air chamber and table will rock about the pivots I56, and the inclination of the table will be varied or regulated as desired.

In Fig. 9 of the drawings, a different form of means for regulating the discharge of the rock or other stratified heavier material is shown, likewise preferably located at the central forward end of a particular separating zone or area of the table. In this form of device, a gate I80 is provided at the discharge port or opening 51, the gate being variably positionable so as to permit the discharge of all of the rock and to prevent the discharge of any of the coal. As embodied, the gate I86, which is of substatnially the width of the opening 51, is pivotally mounted at its bottom by a hinge I8I, mounted upon the table structure 39.

To variably position the gate I80, as embodied, a link I82 is pivotally connected to the gate I83, and at its other end I89, the link is pivotally connected to an arm I85, fixed on a shaft I86, which shaft is journaled in bearing brackets I81, mounted on the side wall of the chamber 19. On the exterior of the air chamber are provided means for moving the gate I80 and holding it in proper position, and, as embodied, a lever arm I68 is fixed to the shaft I86, and cooperates with a locking sector I89. Thus the flow of the separating and Stratified rock, or other heavier material, through the port 51 is regulated in exact accordance with the separating action of the corresponding table area.

In accordance with one feature of the invention, means are provided for practically immediately discharging from a separating area 39 of the table, the superior stratified and separated layer of coal or other lighter material, and this means may be constructed and arranged to completely or partially effect the discharge of such light material, in so far as it may be completely separated at this part of the table. In Figs. and 11 of the drawings, is shown an embodied form of deflector devices, which are variably positionable both vertically and horizontally, and as to inclination and length, to secure the separating and discharging action which may be most efiicacious with any particular kind or condition of intermixed materials undergoing separation.

As embodied, deflector strips I96 and I91 are shown at either side of the table, these strips being forwardly and outwardly inclined, and having their forward and exterior ends terminating at the forward ends of corresponding ports I98 and I99, formed in the respective side walls 45 and 45 of the table. These deflector strips are vertically positionable by suitable means, such as bolt and slot connections 206 and 20I, with brackets or standards 202 and 263, conveniently mounted upon the table itself or on the side wall structure. The standards 262 and 293 may be variably positionable upon the face of the table, to vary the angular disposition of the deflecting strips I96 and I91, as may be found desirable to secure the best results with any particular materials or under any given conditions of the separating work. Means are preferably provided also for varying or regulating the discharge of the materials through the ports I98 and I99, and as embodied, slides 296 and 281 are provided, respectively, at the bottom sides of ports I96 and I99, and these are vertically variably positionable, by bolt and slot mountings 269 and 269, on the exterior of the vertical walls 45 and 95 of the table.

At the left-hand part of Fig. 10, the deflecting strips I96 and I91 are shown of considerably greater length, and approximately meeting at the longitudinal center line of the table. In the case of deflecting strips first described, the central portion of the superior stratum flows forwardly along the table from one separating area to the next following separating area, while with the arrangement shown at the left-hand end of Fig. 10, the superior stratum is practically completed deflected and discharged, to a predetermined depth, dependent upon the depth of the completely pure stratum of the lighter and superior material.

It will be understood that these devices will be coordinated with the feeding-on means, especially if the broad sorting means, previously described, is also utilized. That is, the feeding on of sorted material and the deflecting strips will be positioned so as not to interfere one with another. When desired, any portion of the area within and between the deflecting strips and the side wall of the table may be rendered air impervious, as by laying a metal plate of the right size or shape over that portion of the airpervious table.

When the side discharge means are employed, there are provided also chutes ZI I, 2I2 at either side of, and just exteriorly to the side walls 44 and 45. These chutes deliver the coal into a final delivery chute 2I3 at the forward end of the table, which in turn delivers the coal upon the conveyor belt H3.

In the operation of the device, it will be understood that the use of the different instrumentalities will be regulated and coordinated, dependent upon the kinds and conditions of the intermixed, divided materials to be separated.

In the capacity for varying the manner and degree of correlation and cooperation of the various instrumentalities to meet the varying requirements of successful and approximately complete separation with different kinds and conditions of intermixed materials lies in part the value of the invention.

The table may be assumed to be in operation, with a bed or series of sub-beds of intermixed, divided materials thereon, gradually undergoing Stratification and separation. The materials will be fed continuously to the bed or sub-beds at such rate as will maintain said bed or sub-beds of materials of the desired thickness upon the table, the materials gradually traveling forwardly and becoming more and more completely separated. When the first system is employed, all the intermixed unsized raw coal is fed to the rear end of the table and travels therealong over the successive separating zones as a continuous and progressively separating bed, the air currents and other instrumentalities being regulated to effect the most efiicacious separating action with the particular coal being acted upon. The fiotant superior stratum of coal or lighter material may be caused to travel the length of the table and all discharged at the forward end thereof, or alternatively, some or all of said fiotant stratum of coal may be discharged laterally at the ends of the successive zones as hereinbefore described.

When the screen, or other broad sorting device 20 is employed, as in the second and third systems, it can be arranged to deliver a fairly wide range of sizes at the rear end of each separating area or zone of the table. The delivery of the material to the table may be entirely across the width thereof, or may be only to the central part thereof, as might be the case with the use of the deflecting strips of a certain type, such as shown at the left-hand end of Fig. 10.

The hopper and screen may be also positioned relatively to the table, so that either the smaller sizes may be delivered to the rear separating area and larger sizes to the areas respectively forwardly, or vice versa, thereby providing for operation of either the second or third systems respectively. Likewise, the degree of airperviosity may be varied in the different separating areas of the table, and with certain intermixed materials, it is more eflicacious to have the air-perviosity of the table increasing gradually forwardly, either from zone to zone, or also gradually within or throughout the particular zones.

As the stratifying and separating actions proceed, the purified coal forms into a superior stratum, and the rock or other heavier material in a given zone will settle upon the table, will be forwarded by friction and inertia, and will be concentrated at the central forward end of the separating zone, and will pass out through the port 57, the regulating means at the port being set so as to permit the discharge of all of the separated rock and to prevent the discharge of any of the coal. The action of the table in this wise may be very carefully inspected by watching the chambers 19 and 85.

The coal or other superior stratum of separated material will flow forwardly over the deflecting walls 58 and 59 for the rock or other heavier material, and will pass forwardly along the table. In so far as this upper stratum is completely separated, the deflecting strips may be set to immediately discharge it from the sides of the table, and again this capacity will determine the variable position of the deflecting strips, and also the sizes of the ports I98 and I99 so as to render it possible to discharge all the completely separated coal, and to permit any still intermixed portion of materials to pass onwardly into the next separating area, to be subjected further to the stratifying action.

Alternatively, by using the variably positionable deflecting strips I96 and 191 shown at the right hand end of Fig. 10, a regulable portion of the flotant superior stratum of fine coal may be permitted to progress from the rear separating zone 39 onto the next separating zone 39a and intermix with the sub-bed of intermediate-sized material fed thereto from the sorting device. Thus the amount of fine particles which is introduced into the sub-bed of raw coal on the separating area 39a and/or into the sub-bed on the area 3% may be very nicely controlled and proportioned, as may be found desirable to secure the best results with any particular materials or under any given conditions of separating work, and the relative quantities of the different sizes in intermixture in the successive sub-beds can be regulated as found most efficacious in practice.

It will be understood that the foregoing is a general outline of the actions of the table under certain conditions and is explanatory of one manner of operating the table, i. e., the second system, but is not restrictive as to the uses of the table or as to all conditions and actions of different kinds of intermixed materials undergoing separation.

Referring now in detail to the operation of the third system, the sorting mechanism 20 is shown in Fig. 12 in position to deliver the coarsest size range of intermixed materials from the mass of raw coal to the rear or first separating zone 39, an intermediate size range being delivered to the intermediate zone 39a and the finest intermixed materials to the forward separating zone 39b. By analogy to the second system, the coarser materials undergo a separate pneumatic-stratification separating action in the initial sub-bed 39 and the coarse impurities are separately discharged at the forward end of said subbed. All of the superior or flotant stratum of material may be delivered forwardly from the rear subbed 39 into the intermediate sub-bed 39a and successively into the forward sub-bed 39b as the continuous stratifying and separating process progresses. Alternatively and optionally, the entire fiotant stratum at the forward ends of the separating zones or sub-beds 39 and/or 39a may be successively deflected and discharged laterally by the deflecting strips. As a third alternative procedure, a regulable portion of the coarse flotant material from the rear zone 39 may be introduced into the intermediate zone 39a andsimilarly a regulable portion of the coarse and intermediate sized lighter materials from zone 39a may be introduced into the forward separating zone or sub-bed 3%. Thus the relative proportions of the different size ranges in the various sub-beds may be carefully regulated and controlled in the various successive sub-beds as desired in reverse order to the sequence of the second system.

The invention in its broader aspects is not limited to the specific mechanisms shown and described but departures may be made therefrom within the scope of the accompanying claims without departing from the principles of the invention and without sacrificing its chief advantages.

What I claim is:

1. The process of purifying a mass of raw coal comprising intermixed pieces and particles varying relatively widely in size, which includes subjecting a part of said raw coal to successive pneumatic-stratification separating operations, one of said separating operations treating a. bed comprising in intermixture all sizes of the coal in said raw mass, and another separating operation treating a bed comprising in intermixture only the finer sizes of said raw coal.

2. Process of purifying a mass of raw coal comprising intermixed pieces and particles varying relatively Widely in size, which includes subjecting a part of said. raw coal to successive pneumatic-stratification separating operations, one of said separating operations treating a bed comprising in intermixture all sizes of the coal in said raw mass, and another separating operation treating a bed comprising in intermixture only the finer sizes of said raw coal which have been passed through a screen of predetermined size.

3. The process of purifying a mass of raw coal which comprises subjecting the coal to size classification into a plurality of sub-size ranges, subjecting different sub-size ranges to dry pneumatic separation in different beds, a finer size range being subjected to dry pneumatic separating action in a plurality of said beds in one of which a larger sub-size is being pneumatically separated.

4. The process of purifying unsized coal which comprises subjecting various sub-size ranges to dry pneumatic separating action in different beds, a finer size range being subjected to dry pneumatic separating action in a plurality of said beds.

5. The process of purifying unsized coal which comprises subjecting various sub-size ranges to dry pneumatic separating action in different beds, at least a portion of a finer size range being subjected to dry pneumatic separating action in a plurality of said beds.

6. The process of purifying a mass of raw coal containing intermixed pieces and particles varying relatively widely in size, which comprises subjecting a predetermined size range of the coal from said mass to successive pneumatic stratification separating actions, one of said separating actions being applied to a bed containing in intermixture all sizes of the coal in the raw mass during which separating action the fines assist in the purification of the coarser sizes: while themselves being purified, and another separating action being applied to a bed containing in intermixture only the coal and refuse from the mass within said predetermined size range whereby said size range receives additional or protracted treatment.

'7. The process of purifying a mass of raw coal containing intermixed pieces and particles varying relatively widely in size, which comprises subjecting a predetermined size range of the coal from said mass to successive pneumatic stratification separating actions, one of said separating actions being applied to a bed containing in intermixture all sizes of the coal in the raw mass during which separating action the fines assist in the purification of the coarser sizes while themselves being purified, and another separating action being applied to a bed containing in intermixture only the coal from the mass within said predetermined size range, and transferring said size range of coal from one bed to the other whereby said size range receives additional or protracted treatment.

8. The process of purifying a mass of raw coal comprising intermixed pieces and particles varying relatively widely in size, which includes subjecting a part of said raw coal to successive pneumatic stratification separating operations, one of said separating operations treating a bed comprising in intermixture all sizes of the coal in said raw mass during which separating operation the fines assist in the purification of the coarser sizes while themselves being purified, delivering from said bed the coarser pieces of the heavier material as a separate product, and another separating operation treating a bed comprising in intermixture only the finer sizes of said raw coal whereby the finer sizes receive additional or protracted treatment.

9. The process of purifying a mass of raw coal which comprises maintaining a bed of coal of a relatively wide size range undergoing a pneumatic stratification separating action, and introducing into said bed a controllable quantity of coal of a limited size range to be itself concurrently purified and to act as an agent in purifying said wide size range and thereby varying the relative proportions of the sizes in said bed from those naturally in the raw coal.

10. The process of purifying a mass of raw coal which comprises maintaining a bed of coal of a relatively wide size range undergoing a pneumatic stratification separating action, and introducing into said bed coal of a limited size range, from which at least a portion of the original impurities have been removed, to be itself concurrently further purified and to act as an agent in purifying said wide size range and thereby varying the relative proportions of the sizes in said bed from those naturally in the raw coal.

11. In the process of purifying coal, the steps of maintaining a bed of impure coal containing a range of finer sizes undergoing a pneumatic stratification separating action, and introducing into said bed coarse coal in controllable amounts to be acted on by the finer sizes in said bed as an active processing agent and thereby varying the relative proportions of the sizes in said bed from those naturally in the raw coal.

12. The process of purifying a mass of raw coal which comprises feeding a portion of said mass to a bed containing a relatively Wide range of sizes, subjecting said bed to a pneumatic stratifying and separating action wherein the finer sizes assist in the purification of the coarser sizes while themselves being purified, feeding another portion of said raw mass to a second bed containing a finer size range, and feeding a separated product of the second bed to the first bed to receive additional processing while assisting in the purifying process of the first bed as aforesaid.

13. The process of purifying a mass of raw coal containing intermixed pieces and particles varying relatively widely in size, WhlCh comprises subjecting a predetermined sub-size range of the coal from said mass to successive pneumatic stratification separating actions, one of said separating actions being applied to a bed containing in intermixture all sizes of the coal in the raw mass and employing relatively great air intensity wherein the fines assist in purifying the coarser sizes while themselves being purified, and another separating action being applied to a bed containing in intermixture only the coal and refuse from the mass within said predetermined sub-size range and employing a lesser air intensity to give additional or protracted treatment to said predetermined size range.

14. The process of purifying a mass of raw coal comprising intermixed pieces and particles varying relatively widely in size, which includes subjecting a part of said raw coal to successive pneumatic stratification separating operations, one of said separating operations treating a bed comprising in intermixture all sizes of coal in said raw mass and employing relatively great air intensity wherein the fines assist in purifying the coarser sizes While themselves being purified, and another separating operation treating a bed comprising in intermixture only the finer sizes of said raw coal and employing a lesser air intensity to give additional or protracted treatment to said predetermined size range.

15. A process of purifying a mass of raw coal comprising intermixed pieces and particles varying relatively widely in size, which includes subjecting a part of said raw coal to successive pneumatic stratification separating operations, one of said separating operations treating a bed comprising in intermixture all sizes of the coal in said raw mass and employing a relatively great air intensity wherein the fines assist in purifying the coarser sizes while themselves be ing purified, and another separating operation treating a bed comprising in intermixture only the finer sizes of said raw coal which have been screened to a predetermined size and employing a lesser intensity to give additional or protracted treatment to said finer sizes.

16. The process of purifying a mass of raw coal which comprises the steps of concurrent size classification into sub-sizes, pneumatically purifying different sub-sizes in different beds, a finer sub-size being present in a bed containing a larger sub-size during pneumatic purification of said larger sub-size said finer sub-size participating as an active agent in the purification of said larger sub-size While itself being purified.

17. The process of purifying a mass of raw coal which comprises the steps of concurrent size classification into sub-sizes, pneumatically purifying different sub-sizes in different beds, a finer sub-size being present in a bed containing a larger sub-size during pneumatic purification of said larger sub-size and participating as an active agent in the purification of said larger sub-size while itself being purified, and employing different air intensities for the pneumatic purification in the different beds.

18. The process of purifying a mass of unsized raw coal containing intermixed pieces and particles varying relatively widely in size which comprises maintaining a plurality of beds undergoing pneumatic stratification separating action, in one of which beds the wide size range is treated in intermixture and where particles or pieces of varying sizes may interact during said separating action and in another of which beds a narrower size range is subjected to separating treatment additional to that received in the other bed.

19. A mechanism for separating intermixed divided materials including in combination a table having a plurality of air-pervious separating zones disposed longitudinally thereof, means for supplying and maintaining a bed of the materials upon the table undergoing separation.

including devices for supplying the intermixed materials sorted as to size to different separating zones of the table, means for stratifying and separating the materials including devices for forcing air through the materials of the bed. and means at the end of a separating zone for immediately discharging an inferior heavier stratified material at rest upon the table.

20. A mechanism for separating intermixed divided materials including in combination a table having a plurality of air-pervious separating zones disposed longitudinally thereof, means for supplying and maintaining a bed of the materials upon the table undergoing separation, including devices for supplying the intermixed materials sorted as to size to different separating zones of the table, means for stratifying and separating the materials including devices for forcing air through the materials of the bed, means at the end of a separating zone for immediately discharging an inferior heavier stratified material at rest upon the table, and means for discharging a superior lighter layer of separated and stratified material.

21. The process of purifying raw, substantially unsized coal which comprises maintaining a bed including in intermiXture the coarse coal and impurities of said coal, separating the coarse pieces of heavy material by subjecting said bed to pneumatic separating action and delivering said coarse heavy material as a separate prodnot, subsequently delivering coarse coal as a separate purified product, delivering the unpurified portion of said bed to a second bed containing intermixed finer coal and impurities screened from the mass of raw unsized coal and subjecting said second bed to a separate pneumatic cleaning action to separate the residual heavy impurities therefrom.

22. A mechanism for separating intermixed divided materials including in combination a table having a plurality of air-pervious separating zones disposed longitudinally thereof, means for supplying and maintaining a bed of the materials upon the table undergoing separation, including devices for supplying the intermixed materials sorted as to size to different separating zones of the table, means for stratifying and separating the materials including devices for forcing air through the materials of the bed, and means at the central part only of the end of a separating zone for immediately discharging an inferior heavier stratified material at rest upon the table.

23. A mechanism for separating intermixed divided materials including in combination a table having a plurality of air-pervious separating zones disposed longitudinally thereof, means for supplying and maintaining a bed of the materials upon the table undergoing separation, including devices for supplying the intermixed materials sorted as to size to diiferent separating zones of the table, means for stratifying and separating the materials including devices for forcing air through the materials of the bed, means at the end of a separating zone for immediately discharging an inferior heavier stratified material at rest upon the table, and means for discharging a superior lighter stratified material at the ends of successive separating zones.

24. The process of purifying a mass of substantially unsized coal containing in intermixture relatively large pieces and fine particles which comprises maintaining a bed of said coal containing pieces from the maximum size down to the finest particles, vibrating the bed and passing lifting and loosening air current therethrough, and thereby removing the larger pieces of heavy material as a separate product, and further purifying the finer particles of the mass by subjecting only the finer coal and fine intermixed impurities in a separate bed of lesser size range to a similar vibration and air action to remove the fine heavy material from the fine coal, and separately delivering said fine heavy material.

25. The process of purifying a mass of raw, substantially unsized coal which comprises subjecting a bed thereof to vibration and lifting and loosening air currents and separating the large heavy pieces of said mass from the bed containing all sizes of coal including the largest pieces to the finest particles and delivering said large heavy pieces as a separate product, while the purifying action upon the fine particles of the mass is made relatively more extensive by maintaining a separate bed comprising only the finer particles of the mass and delivering the fine heavy material from said bed as a separate product.

26. A mechanism for purifying raw coal including in combination a vibratable, air-pervious table supporting a bed of the coal undergoing stratification and separation above the table, means for discharging the separated pure coal and impurities from the bed and above the table, means for effecting size classification of the raw coal and feeding different sizes thereof to different parts of the bed upon the table whereby difierent size ranges are subjected to stratifying and separating treatment for different lengths of time.

27. A mechanism for purifying raw coal including in combination a vibratable, air-pervious table supporting a bed of the coal undergoing stratification and separation above the table, means for discharging the separated pure coal and impurities from the bed, means for effecting size classification of the raw coal and feeding different sizes thereof to different parts of the bed upon the table whereby different size ranges are subjected to the stratification and separation treatment for different lengths of time, means for forcing loosening and lifting air currents through the bed, and means for regulating the intensity of the air current action in different parts of the bed whereto the different sizes of raw coal are fed.

28. A mechanism for purifying raw coal including in combination a vibratable, air-pervious table supporting a bed of the coal undergoing stratification and separation above the table, means for feeding different sizes of raw coal to different parts of the bed upon the table whereby different size ranges are subjected to stratification and separation in different parts of the bed, means for forcing lifting and loosening air currents through the bed, and means for discharging settled impurities from the top of the table at different points longitudinally of the bed.

29. A mechanism for purifying raw coal including in combination a vibratable, air-pervious table supporting a bed of the coal undergoing stratification upon the table, means for feeding different sizes of raw coal to different parts longitudinally of the bed upon the table, means for forcing, lifting and loosening air currents through the bed, means for regulating the intensity of the air current action in different parts of the bed whereto the various sizes of coal are fed, and means for discharging settled impurities at different points longitudinally of the bed.

30. The process of purifying substantially unsized coal which comprises supporting, vibrating and progressing a bed of the coal while forcing lifting and loosening air currents through the bed to stratify and separate the pure coal and impurities in the bed, preliminarily effecting a size classification of the impure coal and feeding different sizes thereof at different points to said bed whereby different size ranges are subjected to stratifying and separating action for different lengths of time, delivering the stratified pure coal and impurities separately from the bed and regulating the intensity of the air current action in relatively small sub-areas of the bed whereto the various sizes of raw coal are fed.

31. A mechanism for purifying coal including in combination an air-pervious deck, means for feeding different sizes of coal to different parts of the deck, means for conveying coal of one size range from one part of the deck to another part thereof containing a different size range, and an air chamber having a plurality of compartments, and means for regulating the intensity of the air currents within the various compartments to vary the air current intensity through the different parts of the bed to which the different sizes of coal are fed.

32. The process of purifying substantially unsized coal which comprises supporting, vibrating and progressing a bed of the coal while forcing lifting and loosening air currents through the bed to stratify and separate the pure coal and heavy impurities in the bed, the settled heavy impurities progressing on the support by friction and inertia, arresting said movement of the settled heavy impurities medianly of the bed and permitting the forward movement of the superior stratum and discharging the pure coal from the top level of the bed only and effecting size classification by screening to treat different size ranges in various parts of said bed, and to treat the finer sizes of the unsized coal throughout the bed.

33. The process of purifying substantially unsized coal which comprises supporting, vibrating and progressing a bed of the coal while forcing lifting and loosening air currents through the bed to stratify and separate the pure coal and heavy impurities in the bed, the settled heavy impurities progressing on the support by friction and inertia, regulably discharging settled heavy impurities from beneath and at a median point of the bed, and permitting the forward movement of the superior stratum and discharging the pure coal from the top level of the bed only and effecting size classification by screening to treat different size ranges in various parts of said bed, and to treat the finer sizes of the unsized coal throughout the bed.

34. The process of purifying substantially unsized coal which comprises maintaining and pneumatically treating a forwardly moving bed of coal undergoing purification by stratifying and separating action, offering obstruction transversely of and at different points along the bed to the lower stratum while permitting free movement thereover of a superior stratum, and supplying impure coal of different sizes to different parts longitudinally of the bed.

35. The process of purifying coal pneumatically which comprises maintaining a bed of coal undergoing progressive purification by vibration and the action of air currents, and supplying different sizes of the impure coal to different parts of said bed, stratifying and separating different size ranges within the bed and in different parts thereof, and merging said sizes in the bed as the purified action progresses and progressing settled refuse along the bed supporting deck and discharging the refuse from the upper surface thereof.

36. The process for pneumatically purifying unsized coal comprising the steps of separating and separately delivering the larger pieces of the heavier refuse from a bed containing large pieces and fine particles of coal and refuse by subjecting the bed to vibration and passing air therethrough, and separately pneumatically treating the finer sizes comprised in the first mentioned bed in another bed containing in intermixture only fine coal and fine refuse.

3'7. A mechanism for purifying unsized raw coal including in combination air pervious means for supporting a plurality of beds undergoing pneumatic stratification treatment and screening means cooperating therewith to maintain beds of different size ranges undergoing pneumatic stratification treatment, and means whereby a subordinate size range is passed from one bed to another whereby said subordinate size range is processed for a longer time.

38. A mechanism for purifying unsized raw coal including in combination air pervious means for supporting a plurality of beds undergoing pneumatic stratification treatment and screening means cooperating therewith to maintain beds of different size ranges undergoing pneumatic stratification treatment, and means whereby a subordinate size range of purified coal is passed from one bed to another whereby said subordinate size range is processed for a longer time.

39. The process of pneumatically purifying un sized raw coal of wide size range, which comprises maintaining a plurality of beds of impure coal including one of wider size range and one of lesser size range, pneumatically purifying said wide size range in one of said beds, pneumatically purifying said narrower size range in another of said beds and conveying treated coal from one of said beds to another whereby said treated coal may be treated in both of said beds while constituting a part of the size range of each of said beds.

&0. The process of pneumatically purifying unsized raw coal of wide size range, which comprises maintairnng a plurality of beds of impure coal including one of wider size range and at least one of lesser size range, pneumatically purifying said wide size range in one of said beds, pneumatically purifying said narrower size range in another of said beds and conveying a lesser size range from one of said beds to another whereby said lesser size range may be treated in both of said beds while constituting a part of the size range of each of said beds and supplying raw coal directly to one of said beds.

41. The process of purifying coal which comprises subjecting a mass of raw coal, which contains relatively coarse coal and impurities, to a pneumatic stratifying and separating action, introducing coal of a relatively fine size range to participate in the stratification and separation of said coarser sizes and varying the relative proportions of fine and coarse sizes subjected to the separating action from those naturally in the raw coal.

42. The process of purifying coal which comprises subjecting a mass of raw ,coal, which contains relatively coarse coal and impurities, to a pneumatic stratifying and separating action, introducing coal of a relatively fine size range to participate in the stratification and separation of said coarser sizes, said relatively fine range of sizes having previously undergone treatment to at least partly remove impurities therefrom, and varying the relative proportions of fine and coarse sizes subjected to the separating action from those naturally in the raw coal.

43. In the process of purifying raw coal the steps of subjecting the raw coal first to a screening action whereby the coarser sizes pass over the screen, subjecting the finer material which passes through the screen to a pneumatic separating action on an air-pervious deck, then discharging material from said deck onto a second deck and into intermixture with the coarser material which passed over the screen and completing the separation on said second deck.

REMBRANDT PEALE, JR. 

